Snap switch



June 24, 1952 R, E, PROU-ry 2,601,556

SNAP SWITCH Original Filed 001'.. 5l, 1947 22'57- l j ffy@ 2 4Z 42 C? O 39 .3f f2 y 4/ 3 f2 4f ZZ 4 /6' r I 3/ 26 G L, f2 35 3.5L g 33 26 ,4 "i2, i O

/8 t J T3 4; y l: 2/ zo /g 43 23 48 [6, 23 v /3 I3 55 a a @f3- 2@ @y 4 Z7 58 29 35 34% 2? 57 l? 32 2 [7 56 46 5 4@ 7 @L 'I f// 4u 30 "5 222/ jizz/rean obelfprozfy Patented June 24, 1952 unirse sfmrfes PATENT orsicfa Robert E.' Prouty, Eogansport, Ind., assignorJ to Essex.y Wire Corporation; Logansport; Ind., a cornea-ation', of." Michigan lIliiilfillapplication.October 3L 1.94.7', SeriarLNQ.,

783,412; Divide and this application August' 30;,195'0,l Serialf'No; 182,207'.

(Cl. 20G-67) Claims 1 MyV invention. relates, generally,l to: circuit` in.- terrupters, and it. has particular' relation to `switches of' the. snap acting' type. More. speciiically.,l it. relates to the. provision of manually operable resettingv means.v for:y the. thermal'. relay disclosed in my copending application,. Serial No. '783,411 filed October 31', 1947,. now abandoned, and. assigned tothe assigneerof. thisapplication, and further my present application constitutes a:v divisional application of my cepending application, Seriali No. 783,412, filed October 31', 1947', now Patent No. 2,54.I,1'71, being dirooted'y to thev species of switch displayed in Figures 3. and 4 of the latter referred to and this present application.

Among' the: objects off my: invention are: 'To maintain` a thermally operable overload protector relay: in` the ope-rated position once it has operated' in response to an overload; to reset such a relay to the normal operative position; to employ ank actuator operating through a permanent magnet and carrying an armature forcontrolling the iunctioningoil the relay contacts; to provide a self-closingv switch that is manually operable tothe openV position; and to hold the switch in either the closed ory open position by the cooperation of a pairl of' arma-- tures and a permanent; magnet andto move the same from one position to the other by manually operable push buttons;

Other objectsy of myinvention will, in part, be obvious and. in part appear hereinafter.

My invention i's disclosed in the embodiments thereof shown in the accompanying drawing, and it comprises the features off construction, combination of! elements and arrangement of part-s which will be exemplified in the constructions hereinafter set` forth and) the scope of the application ot which will be indicatedin the appendedv claims.

For a more complete understanding of the nature. and scope ofv my invention reference may be had to the following detailedv description, taken togethery with the accompanying drawing, inzwhich:

Figure 1 is a detail' sectional view taken along the line I-l of: Fig-ure 2. andv illustrating how the thermal overload relay disclosed in my copending application, above refer-red to, can be constructed so that it remains in the operated position when it has been operated in response to an overload and arranged' to be, ree stored to the original position by operation of a push button;-

1 Figure z .is a detail sectional. view taken along 2 the line 2-.2 of Figure l, showing the switch construction in-` irontelevation:

Figure 3 is ay view, similar to Figure 1f, but showing a self-closing switch employing aparmanentmagnet and. an armatureto control the operation oi' the switch contacts as permitted by a manually operable push button; andi Figure 4 is a view, similar'to Figure 1', showing a magnetic control; which. is operative to. either position of' the switch contacts: and which includesa. pair of manually. operable push buttons for operating the switch contacts. in opposite directions;

Referring now'` particularly to Figures 1 and 2? of the drawings, it-.Willf be noted that thev refeA erencecharacter Ul. designates, generally, a.. resettable thermal overload' protector relay in which the present invention is'y embodied. The relay Inv cank be employed, as described inmy copending:r application. above. referred to, in conjunction withY a. motor starting relayi'or pro-1 testing' the motor from being subjected to overloads. The relayy lll isf constructed so as to: require. manual resetting; once it: has operated.

The,- relay ll'lis` provided with'. a housing or case ll of insulating material', suchI asa phenolic condensation product. It has. integrallyn formed foot portions l2 and a cover t3. formed? of' the same material. andi secured thereto. byv tubular rivets Hl. Screw. terminals l5, only one of which is illustrated inv Figure 1, are. provided on.: the case; ll; for: making. external connections. to the relay.A lll..

Within: the housing or case. llt there is. located a support l5 of insulating material, such as a phenolicl condensation product, and it carries near one, end a. conductor stripv |18 which may bev connected to one of the sore-vrl terminals I5 by a lead I.9 and to which mayr be secured! a contacty 2'0, preferably in the formy of a silver button. The stationary contact 2U. is arranged to: bel engaged normally byaI movable contact 2:!"y also. preferably a silver button. The mov-- able con-tactr 214 is. carried by ay spring 2'2; which may be anchored in cantilever fashion to a bracket 2&1 that. in turn is secured to the support lli'. The bracket` 23 preferably is constructed as described in detail. in my said copendingapplication and is provided with an adjusting screw il;v which` serves; to change thel biasing force exerted by the'spring ZZfas will be: understooci readily.

In order to move the spring ZZ` for the purpose of separating the contacts 2U and 2l. `an aotniator lllis employed' in the form of a pin of non-magnetic material, such as aluminum. The actuator 26 is slidably mounted in an aperture 21 in a generally rectangularly shaped permanent magnet 28 having an I-shaped cross section which provides poles 29 and 39 at opposite ends. The magnet 28 is positioned in a generally rectangular opening 3l in the support I6 and is secured in position thereon by plates 32 on opposite sides which are held in place by rivets 33.

At the ends of the actuator 26 stop members 34 and 35 are provided. The stop members 34 and 35 both may be formed of magnetic material to provide armatures for cooperating with the permanent magnet 28. As shown, they are in the form of circular washers. Alternatively, the stop member 34 may be formed of non-magnetic material and the stop member 35 of magnetic material.

The actuator 26 may be moved by a bimetallic strip 38 which is anchored in cantilever fashion to a bracket 39 that is similar to the bracket 23 but on the opposite side of the support I6, as illustrated. An adjusting screw 43 serves to adjust the biasing force applied by the strip 38 and f to change its calibration. Heat may be supplied to the bimetallic strip 38 by a heater element 4I whose terminals are secured to conducting sleeves 42 and 43 that project through the support I6. The sleeve 42 serves in part to secure the brackets 23 and 39 to the support I6. It also interconnects the contacts 2l) and 2| and the heater element 4I in series circuit relation, as shown more clearly in my copending application above referred to. connecting the conductor strip I8 and the sleeve 43 to the external screw terminals I5.

Once the actuator 26 has been moved by the bimetallic strip 38 to open the contacts 2li and 2|, the actuator 26 remains in the operated position, since the armature 35 is held adjacent the poles 29 and 30 of the permanent magnet 28. When this occurs, it is necessary to provide external means for restoring the actuator 26 to the initial position so as to permit the spring 22 to again close the contacts 28 and 2|. For this purpose a push button 46 is slidably mounted in a suitable aperture 41 in the housing or case Il. A spring 48, held by a rivet 49, serves to bias the push button 46 to its outermost position.

In operation, on the occurrence of an overload as a result of which suilicient heat is app-lied to the bimetallic strip 38 to move the actuator 25 sufliciently to open the contacts and 2l with a snap action, the circuit there through is opened and, if the relay I0 is connected in series with a motor or like electric device, the energizing circuit thereto is opened. While heat is no longer applied to the bimetallic strip 38 and it returns to its initial position, the actuator remains in the operated position by the attraction of the stop member or armature to the permanent magnet 28. If the stop member 34 is also formed of magnetic material, there is an appreciable time delay before the actuator 26 is moved by the bimetallic strip 38 over that which is provided when the stop member 34 is formed of nonmagnetic material. By depressing the push button 4G either manually or by a machine part, the actuator 26 is moved so as to separate the armature 35 from the permanent magnet 2S. The contacts 20 and 2| are then permitted to reclose with a snap action and the circuit therethrough is reestablished.

In Figure 3 of the drawing there is illustrated,

Suitable means `are provided for intcri generally, at 5I a reclosing contact mechanical switch which employs certain of the parts used in the switch construction shown in Figures 1 and 2 and described hereinbefore. It will be observed that the contacts 20 and 2l and the spring 22 are located on the opposite side of the support I6 in Figure 3. Also, the stop member 34 is in the form of a non-magnetic washer while the stop Y member 35 is of magnetic material and constitutes an armature for cooperation with the permanent magnet 28. As before, the contacts 20 and 2l are normally closed and held in this position by the spring 22. When the push button 46 is depresed suciently to engage the adjacent end of the actuator 23, it is moved to in turn move the spring 22 and separate the contacts 20 and 2l with a snap action. When the push button 46 is released, the biasing force of the spring 22 and the magnetic attraction between the permanent magnet 28 and the stop member or armature 35 serves to move actuator 26 to the left and close contacts 20 and 2l Ywith a snap action, thereby restoring the switch 5l to the initial condition shown in the drawing.

In Figure 4 a mechanical switch is illustrated, generally, at 55. This switch employes certain of the details shown in Figures l and 2 and described hereinbefore. The mechanical switch 55 is s-o constructed that the contacts 2U and 2l are held in either the open or the closed position and the application of an external force is required for operating them in opposite directions. In this construction both of the stop members 34 and 35 are formed of magnetic material. A second push buton 58 is provided and slidably mounted in an aperture 51 in the cover i3. The push button 56 is carried by a spring strip 58 which is secured by a rivet 59 to 4the cover I3. The spring 58 serves to restore the push button 55 to the position shown in the drawing when the'pressure applied thereto is removed.

When the switch is positioned as shown in Figure 4, the application of suilicient pressure to the push button 46 moves the actuator 26 to the right. This separates the stop member or armature 35 from the permanent magnet 28 and causes the spring 22 to move the contact 2l away from the stationary contact 26 with a. snap action. The stop member or armature 34 is moved partly as a result of the movement of the push button 46 and partly as a result of attraction by the permanent magnet '28. It is held against the permanent magnet 28 and the contacts 2U and 2l remain separated after the pressure applied to the push button 43 is removed.

Now when pressure is applied to the other push button 56, it moves the spring 22 and the actuator 26 to the original position shown in the drawing Where the contacts 2U and 2l are closed with a snap action and remain in the closed position.

Since certain further changes can be made in the foregoing constructions and different embodiments of the invention can be made without departing from the spirit .and scope thereof, it is intended that all matter shown in the accompanying drawing and described hereinbefore shall be interpreted as illustrative and not in a limiting sense.

I claim as my invention:

l. In a switch, in combination, a generally rectangular permanent magnet having an I- shaped cross section with the ends forming opposite poles and an aperture inthe interconnecting portion, a non-magnetic actuator movable through said aperture, armatures carried by said actuator for attraction by opposite sides of said magnet, a pair of relatively movable contacts one cooperating with said actuator for movement relative to the other contact, and a pair of manually operable push buttons for moving said actuator from one position to the other to move one armature away from said permanent magnet and the other toward the same and for operating said one contact from one position to the other.

2. In a switch, in combination, a single Wall support, a bracket fastened to said support, a spring secured in cantilever fashion at one end to said bracket, a pair of contacts one being stationarily mounted and the other being mounted at the other end of said spring for movement therewith and relative to the one Contact, a permanent magnet having an aperture therein mounted in said support, a non-magnetic actuator slidingly journalled in the aperture of said magnet, transversely of said support; an armature carried by said actuator and movable therewith toward and away from said magnet, said actuator cooperating with said spring to eiect movement thereof and of said other contact relative to said one contact, push button means disposed on one side of said support, selectively engageable with one end of said actuator, for manually eiecting axial movement of said actuator in one direction, and additional push button means disposed on the opposite side of said support for likewise effecting axial movement of said actuator in an opposite direction.

ROBERT E. PROUTY.

REFERENCES CITED The following references are of record in the file cf this patent:

UNITED STATES PATENTS Number Name Date 2,145,950 Persons Feb. '7, 1939 2,170,341 -Shaw Aug. 22, 1939 2,313,597 Stimson Mar. 9, 1943 2,339,087 Manta Jan. 11, 1944 2,508,381 Frerer May 23, 1950 2,518,480 Lilja Aug. 15, 1950 

